the alpkit jeans are NOT water proof,but are quite water resistant. If you have no rear mudguard and are getting water sprayed on your arse you will have a wet ares in short order.
however, they are much more comfortable than normal denim when wet, especially if you have lycra under the jeans.
threy also seem to clean up easily compared to normal denim, the silicon must repel dirt more easily.
but they are very baggy at the bottom, and the diamond crotch panel ads more seams to chafe
still the best jeans I’ve ever had though